3RW soft starters

Why 3RW soft starters?

SIRIUS 3RW soft starters are used for a soft start and soft stop of three-phase motors and reliably prevent mechanical stress and line voltage dips that can cause problems in the machine or power supply system. Our comprehensive range of soft starters with intelligent functions offers a softer, more reliable alternative for almost every application. Choose from:

High Peformance Due to its exceptional functionality, the SIRIUS 3RW55 soft starter can solve even the most difficult starting and stopping tasks.

General Performance The SIRIUS 3RW52 soft starter is an ideal alternative to star-delta starters. It covers all drive types.

Basic Performance Due to their compact design, SIRIUS 3RW30/40/50 soft starters are the ideal solution for all standard applications.

Simulations Tools Select the right devices for your application — as a desktop app or optimized for your mobile device.

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Key benefits

Discover compact, cost-efficient solutions

When faced with the challenge of ensuring efficient operation of fixed-speed electric motors, the 3Rw soft starters offer gentle, compact and cost-efficient drive solutions.

Experience electrical ruggedness

All SIRIUS soft starters have a wide-range voltage versions, so that even if there is a voltage dip, the continued operation of the soft starter, the motor and the application is ensured.

Reduce energy losses

The integrated bypass function reduces energy losses during operation without generating additional heat, preventing premature damage or failure of drive train components

Featured capabilities

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EtherNet/IP

SIRIUS 3RW55 soft starter now additionally communicates via EtherNet/IP. This means it is able to communicate with a wide range of process control systems.

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3RW55 soft starters media redundancy

Thanks to the new Profinet High Feature communication module and its integrated ethernet switch, the 3RW55 provides a ring topology in which communication can be maintained via a second port even if the power fails.

Siemens soft starter 3RW55 failsafe with a blue background and white text.

Integrated Safe Torque Off (STO) function

Now integrated into the SIRIUS 3RW55, the Safe Torque Off (STO) function means that in the event of an emergency, you can effectively ensure the drive can no longer supply any torque-generated energy.